Key cutter



'March 26, 1940. H. w; DEVLIN I KEY CUTTER Original Filed April 25. 1933 lnren for: Henry W. Der/in Reissued Mar. 26, 1940 PATENT OFFICE KEY CUTTER Henry Wayne Devlin, Sacramento, to A. K..Underwood, Derive Original No. 1,958,235, No. 667,781, April 25, issue December 15, 1

11 Claims.

This invention relates to a hand operated key cutter, and has for its principal object, the provision of a simple and compact cutting device which can be operated with one hand; which will accurately cut the tumbler pin notches at the proper spacing, and to the proper depth; which can be of use for accurate duplication of keys according to code numbers, and which will occupy no more spacethan an ordinary pair of pliers.

Other objects and advantages reside in the detail construction of the invention, which is designed for simplicity, economy, and efficiency. These will become more apparent from the following description.

In the following detailed description of the invention reference is had to the accompanying drawing which forms a part hereof. Like numerals refer to like parts in all views of the 2 drawing and throughout the description.

In the drawing:

Fig 1 is a perspective view illustrating the improved key cutter.

F'ig. 2 is a longitudinal section therethrough illustrating the interior mechanism.

Fig. 8 is a cross section through the cutting head taken on the line 3-3, Fig. 2.

Fig. 4 is a cross section through the frame cad, taken on the line 44, Fig. 2.

Fig. 5 illustrates a typical key blank. Fig. 6 illustrates a key cut with this improved key cutter.

The invention preferably comprises a hollow frame or hand-grip member Ill terminating in a stationary handle II. A movable handle I2 is pivoted in the frame member ID upon a suitable pivot pin l3. The upper extremity of the movable handle extends within the frame ID to form a. bifurcated operating lever I4. A coil spring I5 is positioned about the pivot pin I3, with its extremities arranged to constantly urge the two handles II and I2 apart.

A cutting head extends forwardly from the frame I0. It consists of a key block frame I6 which may be formed, as illustrated, with an inverted U-shaped outline. One extremity of the key block frame It is permanently riveted into the frame member Ill by means of suitable rivets IT, or it may be otherwise secured therein. The frame I6 is arranged to enclose any desired number of key guide blocks I8. The device, as illustrated, is designed to cut pin notches of three different depths and contains three of the key guide blocks I8 along which a key is moved. Above each of the guide blocks an index numeral Calif., assignor r, Colo.

dated May 8, 1934, Serial 1933. Application for re- 939, Serial No. 309,447

is stamped into the block frame It, as indicated by the numerals 2, 3, and 4 on the drawing.

The guide blocks are maintained in place by means of a cutting rod I9 which extends entirely through the block frame I5 and through each of the guide blocks I8 therein. The outer extremity of the cutting rod is provided with an adjustable stopnut 29. The inner extremity terminates in a rectangular hinge block 2| which is snugly fitted between the furcations I4 of the operating lever I2 and which is secured therein by means of a suitable hinge pin 2Ia.

It will be noted that each of the key guide blocks I8 is formed with a horizontal key way 22 extending entirely across the block. The key ways 22 in the adjacent blocks are positioned at different heights, that is, the key way of block 2 is higher than the key way of blocks 3 and 4.

A notch 23 is formed in the cutting rod at each point where it intersects one of the key ways 22. The notches 23 may be of varied depth corresponding to the varying elevations of the key ways in the key blocks, or, if desired, they may be all of thesame depth. In the latter case, the notches must have a depth equal to that of the deepest notch orcorresponding to the key Way of the lowest elevation. The stop nut 20 should be adjusted-to bring the notches 23 into alignment with the key slots.

It can be readily seen that if a key blank, such as the one indicated at 24, is inserted in one of the key ways 22, and the handles are compressed, the cutting rod I9 will act to punch or cut a, notch in the key edge. This notch formed keyway 2 will be of relatively less depth than the notch which would be formed if the key were inserted in key block 3 or 4, owing to the differing elevations of the keyways. Therefore, the operator can obtain a notch of any of three different depths. l

The notches can be accurately positioned at the proper tumbler positions along the key by means of a series of tumbler spacing stops 25 which are hinged upon a pin 25 extending from the block frame It. The spacing stops 25 are clamped together so as to frictionally engage each other bymeans of a compression spring 21, which is positioned against the outer arm and the head of the pin 25. The frictional engagement of the arms serves to maintain them in any desired position. When swung to a horizontal position beneath the keyways 22, the stops 25 will be engaged by a shoulder 28, with which each key blank is provided, so as to limit the 28 strikes the first stop 25.

distance the key may be inserted in the keyway 22, thus holding the key in a selected position with reference to the keyway and the cutting member.

Let us assume it is desired to duplicate the key illustrated in Fig. 6. The key blank is first inserted in keyway 2, with the stops 25 swung out of the way so that the key may be inserted its full length before the shoulder 28 strikes the key block it. The handles are compressed and the shallow notch a is cut. The innermost stop 25 is now swung to a horizontal position and the key is inserted into keyway 3 until the shoulder The handles are compressed and the medium notch B is cut. The second stop 25 is now swung into position and the shallow notch C is cut in the keyway 2. The third stop is swung into position and the deep notch D is cut in keyway l, as shown in broken line in Fig. 3. The fourth stop 25 is now swung into position and the medium notch E is cut in keyway 3. The resulting key is perfect both as to pin depth and tumbler spacing.

While the keyways illustrated are designed to receive single groove keys of the type illustrated in Fig. 5, it is to be understood that the difl'erent key blocks may be inserted in place of the blocks 18, having keyways contoured to fit different types of keys.

While a specific form of the improvement has been described and illustrated herein, it is desired to be understood that the same may be varied, within the scope of the appended claims, without departing from the spirit of the invention- Having thus described the invention, what is claimed and desired secured by Letters Patent is:

1. A key cutter comprising: a key guide member having a keyway extending therethrough for receiving a key; a cutting member extending through said guide member at right angles to said keyway; means for projecting said cutting member across said'keyway so as to cut a notch from a key therein; means for limiting the amount of insertion of said key in said keyway to any one of a series of predetermined points comprising a series of stop members and means for allowing said stop members to be selectively brought into contact with said key.

2. A key cutter comprising a frame member; a stationary handle projecting from said frame member, a movable handle hinged to said frame member; key guide members carried by said frame member, each provided with a keyway; a cutting member extending through said key guide members and intersecting the keyways therein; a hinged connection between said cutting rod and said movable handle so that as said handle is operated, said rod will be projected across said keyways, there being a notch formed in said cutting rod at the points of intersection of each key channel.

, 3. A key cutter comprising a frame member; a stationary handle projecting from said frame member; a movable handle hinged to said frame member; key guide members carried by said frame member, each provided with a keyway; a cutting member extending through said key guide members and intersecting the keyways therein; a hinged connection between said cutting rod and said movable handle so that as said handle is operated, said rod will be projected across said keyways, there being a notch formed in said cutting rod at the points of intersection of each key channel; and means for stopping the ina stationary handle projecting from said frame member; a movable handle hinged to said frame member; key guide members carried by said frame member, each provided with a keyway; a

cutting member extending through said key guide members and intersecting the keyways therein; a hinged connection between said cutting rod and said movable handle so that as said handle is operated, said rod will be projected across said keyways, there being a notch formed in said cutting rod at the points of intersection of each key channel; and means for stopping the insertion of said key in said key channels at a predetermined point; said latter means comprising a series of independent stop members adapted to be swung to a position opposite the entrance of said key channels.

5. A key cutter comprising: a frame member; a stationary handle projecting from said frame member; a movable handle hinged to said frame member so as to coact with said stationary handle to form a hand grip; guide blocks provided ber, a key guide on the member having a keyway therethrough, a movable cutter extending through said guide member, a handlepivotally attached to said hand-grip member for projecting the cutter across the keyway, and means for limiting the degree of insertion of a key into said keyway with reference to the cutting member to any one of a number of predetermined positions.

'7. A key cutter comprising a hand-grip member, a key guide on the member having a keyway therethrough, a movable cutter extending through said guide member, a handle pivotally attached to said hand-grip member for projecting the cutter across the f keyway, and means inclusive of a stop for limiting the degree of insertion of a key into said keyway to a predetermined position with reference to said cutting member.

8. A key cutter comprising a hand-grip mem-' said guide member, a handle pivotally attached r to said hand-grip member for projecting the cutter across the keyway, resilient means positioned to oppose pivotal movement of the handle, means inclusive of a stop for limiting the degree of insertion of a key into said keyway to a predetermined position with reference to said cutting member, and means for bringing the stop into operative contact with a key.

9. A key cutter comprising a hand-grip member, a key guide carried on the member, a key cutting member positioned adjacent the path of a key being moved along the guide member, a handle pivotally connected with the hand-grip member for projecting the cutting member across the path of a key so moved, resilient means positioned to oppose pivotal movement of the handle, and means inclusive of a series of stops for selectively limiting the movement of a key along the guide member to any one of a number of m means for holding a key in a predetermined position in the keyway.

11. A key cutter comprising a hand-grip member, a key guide on the member having a keyway, a movable cutter extending into said guide member, a handle pivotally attached to said hand-grip member for projecting the cutter across the keyway, resilient means positioned to oppose pivotal movement of the handle, and means for selectively positioning a key in said key guide with reference to the cutter.

HENRY WAYNE DEVLIN. 

